A yard hydrant conventionally includes a discharge nozzle above ground level connected to a standpipe or riser that extends into the ground below the frost line to well known working parts connected to a source of water supply under pressure. When water flow is turned off, residual water within the hydrant is subject to freezing at freezing temperatures. To avoid such freezing, a common expedient has been to provide a “drain hole” below the frost line so the water will drain out into the surrounding ground when the hydrant is turned off. A disadvantage of such a drain hole is the fact that it is also a way for reentry of water into the hydrant which intermixes with other water passing there through. Under such conditions, there is the possibility of contamination of the hydrant water from impure seepage which, if it occurs, can contaminate the water supply. For this reason, many city and rural water supply organizations have regulations prohibiting the use of the aforementioned old “drain hole” technology.
Accordingly, in the hydrant art, structures have been developed which eliminate the drain hole and substitute some form of a storage reservoir/storage chamber structure below the frost line whereby the residual water can be contained and stored below the frost line and subsequently be discharged above ground level the next time the yard hydrant is used to supply water above ground. U.S. Pat. No. 5,261,441 to Anderson and U.S. Pat. No. 5,246,028 to Vandepas and U.S. Pat. No. 5,701,925 to Mulligan et al. show such solutions for sanitary yard hydrants that drain to a reservoir under the frost line instead of using the older drain hole technology. All of the aforementioned patents are incorporated herein by reference in their entirety.
The yard hydrant shown in U.S. Pat. No. 5,246,028 to Vandepas uses a Venturi to siphon water out of the storage chamber but the Venturi only works to pull water from the storage chamber when the hydrant is “full on”. The Venturi needs such high water flow velocity in order to create the siphon necessary to pull the water out of the storage chamber. Because of this situation, the hydrant must be left on for a minute or two each time it is turned on to allow the Venturi to siphon/empty the storage chamber so the storage chamber has enough room to store water from the standpipe/riser each time the water is turned off.
In farm and ranch environments, hydrants are mostly turned on long for a long enough time that the aforementioned problem of getting adequate velocity of the water to make the Venturi work to siphon out the stored water in the storage chamber would not be a problem. But especially in places where members of the public can use a yard hydrant, people will only turn the hydrant on, like for any other faucet, for only the water they need, which quite often is not be enough time for the Venturi to drain the storage chamber, thus leaving water in the standpipe/riser to freeze. The typical use of a hydrant by member of the public that needs only gallon or less of water might mean that that person only turns on a hydrant for less than thirty seconds at a time, which is not enough time for the Venturi to drain the storage chamber in the yard hydrant shown in U.S. Pat. No. 5,246,028 to Vandepas, for example. Since it only takes one time during freezing conditions for the water in the standpipe/riser to not drain and freeze, this is a major problem.
U.S. Pat. No. 5,701,925 to Mulligan et al. was apparently developed, at least in part, to solve the problem discussed above with respect to the yard hydrant shown in U.S. Pat. No. 5,246,028 to Vandepas. In the Mulligan et al. device a second main outlet port was added to allow full flow when the hydrant is first turned on so the venturi will work to siphon out the storage chamber. But this Mulligan et al. design needs an additional component, a vacuum breaker back flow preventer, to be added so flow can be diverted from the second outlet to the first primary main outlet where a hose can be connected. Adequate functioning water flow time through the venturi to create a siphon is still critical in this Mulligan et al. design.
In all of the aforementioned prior art designs, if the water is not allowed to flow freely out the standpipe/riser for an adequate amount of time, the storage chamber will not be emptied, and the next time the yard hydrant is used, the water in the standpipe/riser will have no place to go and will be left above the frost line to freeze.
Accordingly there is a need for a method and apparatus for emptying the storage chamber faster than storage chambers are emptied in prior art sanitary yard hydrants to prevent such hydrants from freezing.
Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. Certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.